At nucleic acid amount less than a nanogram, various “whole genome amplification” (WGA) strategies, such as multiple displacement amplification (MDA) (Dean et al. (2002) Proc. Natl. Acad. Sci. U.S.A. 99:5261-5266, incorporated herein by reference) yield a “background” of undesired amplification products. The ability to efficiently amplify trace amounts of nucleic acids with a minimum of undesired background is highly desirable in research and diagnostic methods, including, but not limited to, clinical, food, environmental and forensic investigative testing.